I have one of these for my dog (https://tryfi.com/ https://tryfi.com/) which has saved my GSD a number of times after running wild out in the woods of Northern

I have one of these for my dog (https://tryfi.com/ https://tryfi.com/) which has saved my GSD a number of times after running wild out in the woods of Northern Michigan. The battery lasts for months in normal operating mode but can be put into "lost mode" remotely where it will ping towers aggressively and give a precise location. This open source solution looks very polished and comprehensive though.